What Causes My Left Hand To Tingle?

(i'm 29, have low thyroid, floaters in my eyes and burning sensations on my skin occasionally..)my left pinky and ring finger along with the palm of my hand are numb and tingly. this has been going on for almost 3 days now and i am really concerned about it. if i rest my elbow on the table (like when putting your head on your hand) i feel a shooting sensation from it to my hand and then my hand begins to tingle. today, however, my hand has tingled constantly without stopping. what is going on?